X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fvmstat.c;h=d7826af2fb073b15e2488470a67ad5a965fa7518;hb=c806e68f5647109350ec546fee5b526962970fd2;hp=b0d08e667ecec2105356fa12bd3a6c77ce2c7e3d;hpb=8ffa5b65968262ba6bb046329972791c0d960745;p=linux-2.6-omap-h63xx.git

diff --git a/mm/vmstat.c b/mm/vmstat.c
index b0d08e667ec..d7826af2fb0 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -516,9 +516,26 @@ static void pagetypeinfo_showblockcount_print(struct seq_file *m,
 			continue;
 
 		page = pfn_to_page(pfn);
+#ifdef CONFIG_ARCH_FLATMEM_HAS_HOLES
+		/*
+		 * Ordinarily, memory holes in flatmem still have a valid
+		 * memmap for the PFN range. However, an architecture for
+		 * embedded systems (e.g. ARM) can free up the memmap backing
+		 * holes to save memory on the assumption the memmap is
+		 * never used. The page_zone linkages are then broken even
+		 * though pfn_valid() returns true. Skip the page if the
+		 * linkages are broken. Even if this test passed, the impact
+		 * is that the counters for the movable type are off but
+		 * fragmentation monitoring is likely meaningless on small
+		 * systems.
+		 */
+		if (page_zone(page) != zone)
+			continue;
+#endif
 		mtype = get_pageblock_migratetype(page);
 
-		count[mtype]++;
+		if (mtype < MIGRATE_TYPES)
+			count[mtype]++;
 	}
 
 	/* Print counts */